1. Field of the Invention
The present invention relates to the improvement in function of a keyboard used as an input device for a computer system.
2. Description of the Related Art
In recent years, notebook personal computers have been required to be, especially, compact and lightweight. For example, regarding the keyboards of notebook personal computers, key arrangements thereof have been modified compared to key arrangements of the keyboards of desktop computers.
The keyboards (hereunder referred to as main keyboards) of notebook personal computers include no independent ten-key pad provided as a key array on a keyboard of a desktop personal computer so as to facilitate the entering of numeric data. Therefore, when a user enters numeric data, usually, he utilizes numeric keys of a key array 11 provided as a part of what is called an xe2x80x9cE-linexe2x80x9d of ordinary character keys (for instance, on the Japanese 109 Keyboard) of the main keyboard, or alternatively, brings the keyboard into a ten key input mode by using a Numlock (or Numeric Lock) function.
The ten key input mode is a mode in which a part of the character keys are changed in function so as to provide a ten-key pad. Generally, the main keyboard is brought into a mode (or an ON mode of Numlock state or status, that is, the ten key input mode), in which the ten key input of data can be performed from a predetermined key array by depressing keys called Numlock keys. When the Numlock key is depressed again, the keyboard is returned to an ordinary state thereof (namely, an OFF mode (hereunder referred to as an ordinary input mode) of the Numlock state).
In the case that the main keyboard is in the ten key input mode, keys for entering character data other than the numeric data are locked in the key array of the main keyboard of the notebook personal computer, and thus cannot be used. Therefore, in the case that character data is inputted from the main keyboard, it is inconvenient that the Numlock function must be canceled by putting the Numlock state into the OFF mode.
Further, external ten key keyboards do not have backspace keys. Thus, in the case that during numeric data is inputted by utilizing the ten key keyboard in the ten key input mode, a cursor is moved and an erroneously inputted character is deleted by using a Delete key or utilizing the Backspace key provided on the main keyboard after this keyboard is put into the ordinary input mode by bringing the Numlock state into the OFF mode to thereby cancel the Numlock function. Therefore, this is inconvenient in the case that character data is erroneously inputted when numerical data is inputted by using the ten key keyboard when a calculator program serving as an application program is utilized.
Accordingly, an object of the present invention is to provide a keyboard improved in operability for key input.
To achieve the foregoing object, according to an aspect of the present invention, there is provided an auxiliary keyboard, which is a first embodiment and is connected to a computer having a main keyboard, which has a main input mode switching key for switching an input mode between a numeric data input mode and a character data input mode, and is provided with a plurality of keys, having a first input mode and a second input mode. This auxiliary keyboard comprises an input mode switching key, mode switching means for switching between the first input mode and second input mode at each depression of the input mode switching key, without indicating the depression to the computer, key code sending means for sending, when the key of the auxiliary keyboard is depressed, a predetermined first key code corresponding to the depressed key of the auxiliary keyboard either in the first input mode or in the second input mode, and mode correcting means for correcting, when the input mode of the main keyboard is switched into the numeric data input mode, the numeric data input mode to the character data input mode.
Further, a second embodiment of the present invention is provided by allocating a second key code, which differs from the first key code, in the auxiliary keyboard that is the first embodiment of the present invention.
According to another aspect of the present invention, there is provided a keyboard that is a third embodiment of the present invention and adapted to assign two functions to one input to have two input modes, in each of which a corresponding one of the two functions is selected, and connected to a computer. This keyboard has the two input modes independently of the computer and comprises mode detecting means for detecting a mismatch between an input mode of the keyboard and an input mode of the computer, and key code sending means for adding, when the mismatch is detected by the mode detecting means and then a specific key having the two alternative input modes is depressed, switch key codes to before and after a key code corresponding to the specific key and for sending the key codes.
According to the first embodiment of the present invention, the function corresponding to each of keys arranged on the main keyboard can be always utilized. Moreover, regarding the auxiliary input keyboard, the mode transition between the first input mode and the second input mode is easily achieved. This results in improvement in operability for input to the computer.
According to the second embodiment of the present invention, a mode, in which the second key code differing from the predetermined ordinary key code is sent only by being processed in the auxiliary keyboard, is established in the auxiliary keyboard. Thus, the function of the auxiliary keyboard can be expanded without affecting the computer and the main keyboard.
According to the third embodiment of the present invention, when the specific key having the selected one of the different two input modes is depressed, it is determined whether or not the switching of the input mode of the computer is necessary. Thus, users can use the ten key keyboard without concern about operating the Numlock key. Consequently, the operability for input to the computer can be improved.